This invention relates to control apparatus for a device, such as an appliance, having a control knob rotatable between an “OFF” and an “ON” position.
It is commonly known to control an appliance such as an oven by means of one or more manually operated controls, including control knobs that can be rotated between “OFF” and “ON” positions. Stoves and ovens that employ natural gas as a heating fuel are commonly used both at home and commercially. One such form of oven that can employ gas as a fuel is a pizza oven and, in particular, such ovens that are large enough and suitable for commercial operators and commercial outlets for pizzas.
A known difficulty that is commonly encountered by the operators of pizza ovens, particularly those at commercial establishments, is that such ovens can require a significant amount of time to heat up to the required temperature. Accordingly, if the oven must be turned on manually by its operator, it is often necessary for the operator to attend at the commercial premises where the oven is located early, that is prior to the establishment opening for business, in order to turn the oven on so that it will reach the required temperature for pizza making when this becomes necessary. This can be a substantial inconvenience to and expense for the operator of the pizza oven. Other types of ovens may also need to be turned on by their operators at a time well in advance of the time at which they will actually be used for cooking or baking.
Although timing devices are common in home baking devices such as ovens, microwave ovens or slow cooking pots, the use of timing devices to turn on large commercial ovens such as pizza ovens is not common at the present time. However, one known timing apparatus for a commercial pizza oven is taught in U.S. Pat. No. 5,464,953 issued Nov. 7, 1995. This U.S. patent teaches a device capable of turning on a pizza oven that has a timer, a solenoid, a toggle switch and a special adaptor plate for mounting next to the control knob which operates the gas valve of the oven. The control knob is spring biased in a rotational direction toward the “ON” position of the knob. The timer is provided to energize the solenoid at a preset time duration, with the solenoid rod being coupled to a pivotable actuating arm, the free end of which is positioned for engagement with a detent formed in the adaptor plate. The toggle switch is in an electrical circuit with the timer and the toggle is physically positioned to be operated by a member projecting from the actuating arm.
More recent U.S. Pat. No. 6,041,768 issued Mar. 28, 2000, describes an oven with an electrical timer for saving and controlling gas. The clock timer is electrically connected to an on/off pilot and gas valve for automatically turning on or off the gas flow to the oven burner. The pilot and gas valve is a known form of electromechanical valve such as that sold by the White-Rodgers Division of Emerson Electric Co.
It is an object of the present invention to provide a reliable control apparatus having a timer which can be used to control a device such as an appliance having a control knob rotatable between an “OFF” and an “ON” position. This apparatus is able to turn on the device or appliance at a selected time and in a reliable manner.
It is another object of the invention to provide a novel control apparatus for a device such as an appliance having a control knob, which can be made at a reasonable cost and using known, readily available components and parts.